Gravity Universe
by RockSunner
Summary: This is a cross-over between "Gravity Falls" and "Steven Universe." The Crystal Gems have come to Gravity Falls to check out a recent energy spike. Can Mabel and Dipper help them save the world?
1. Arrival in Gravity Falls

This is a cross-over between "Gravity Falls" and "Steven Universe." All characters belong to Alex Hirsch and Rebecca Sugar, not me.

**Gravity Universe**

The Crystal Gems transported onto a platform surrounded by thick woods.

"Spread out and keep your eyes open," said Garnet, the tall and taciturn leader with an Afro hairstyle and mirror shades over her three eyes.

"What are we looking for, again?" asked young Steven Universe, the youngest member of the Crystal Gems whose gem powers were still unreliable. Even so, his pluckiness and creativity had proven useful time after time.

"Thirty years ago, we detected a powerful energy spike in this part of the world," said Pearl, the pale and willowy member of the Crystal Gems. She had a sharp nose and a white crystal on her forehead. Her intelligence and grace in battle were extraordinary, although she could get flustered easily. "According to my measurements it was unlike any of our normal sources. We couldn't pinpoint a location then, but recently the spike happened again and the energy flow has persisted, so that we could trace it here."

"Chill, you guys," said Amethyst, the BBW group member with long, flowing purple hair. She tended to be the wild one of the bunch. "These woods look sweet to explore. Let's have fun while we do this."

"I'm with you, Amethyst," said Steven.

"Steven, stick close to her," said Garnet. "This could get dangerous."

"And fun," said Amethyst.

"So what do you guys think is going on?" asked Steven.

"Hybrid technology, perhaps," said Pearl. "A renegade Gem, turned monster, may have illegally shared our technology with humans."

"Isn't sharing a good thing?" asked Steven.

"Our laws say no unnecessary contact with humans," said Garnet.

"I break that by wrestling as the Purple Puma," said Amethyst. "But hey, rules are made to be broken."

"Our ancient structures have built-in wards that turn humans away without them even realizing it, for their own safety," said Pearl. "Remember how the Pizza family said they had never been to our part of the beach, even though it's a small island? They couldn't have come there at all without an invitation from you, Steven."

Steven looked upset, "B-but, what about my Mom? Was her loving my dad illegal? Am I... an unnecessary contact?"

"What Rose did was... unique," said Pearl. "But..."

"The two of you were really pissed when she started dating Greg," Amethyst said. "I was cool with it."

"But now that you're here, we accept you, of course," said Pearl hastily.

"That's creepy," said Steven. "You guys came here from space, put up buildings and had wars all over the place, and you never talked with the people who really belong on this planet? My Mom did the right thing, reaching out to people, and you said it was wrong."

"Steven, you are too young to understand our ways," said Garnet.

"You're right, I don't and maybe I don't want to," said Steven. "Leave me alone! I have to think."

He ran off into the woods. The others were about to follow, when dozens of bull-headed men came out of the woods and surrounded them.

"We Manotaurs don't like it when females pester a boy-child," said the leader. "Attack them!"

Amethyst drew her whip from her gem, Pearl drew her spear from hers, and Garnet activated her power gauntlets.

"I don't detect any gems," said Garnet.

"So they're either rare native fauna or monster-spawn," said Pearl.

Amethyst grinned and said, "Just what we needed, a little combat to work off our frustrations. You boys just bit off more that you could chew."

* * *

><p>Steven ran until he found a road. He followed it to a two-story, run-down wooden building with a sign on top reading "Mystery Shack."<p>

Two kids about his age were playing in the yard, throwing a spinning disk back and forth.

"Hi!" Steven called out. "I'm Steven Universe. Want to be friends?"

"Sure!" said the girl. "I'm Mabel."

"I'm Dipper," said the boy. "Are you a tourist? Where are your folks?"

"I'm with the Crystal Gems," said Steven. "At least, I thought I was but I'm not sure I really belong."

"Is that a band?" asked Mabel. "It sounds like one."

"We have a band," said Steven. "Steven and the Crystal Gems. I play guitar and sing."

"Cool!" said Mabel. "A boy rock star. If you were a little older..."

"Are you guys going to give a concert around here?" asked Dipper

"I wish, but we're here on a mission," said Steven. "We investigate mysteries and save the world from monsters."

"How about that?" said Mabel. "So do we!"

"Really?" said Steven. "You've seen monsters around here? Maybe you could help us."

"Yeah, big time," said Mabel. "Gnomes, vampires, zombies, you name it."

"Mabel, I'm not sure we should talk about this with outsiders," said Dipper.

"You're just like the Crystal Gems," said Steven. "If nobody talks to anybody, how are we going to team up and beat the monsters?"

"All right, I'll give you a chance," said Dipper. "If you want to know about monsters in Gravity Falls, you've come to the right place."


	2. Gems and Glows

**Gems and Glows**

Mabel asked Steven, "How old are you?"

"I'm twelve," he told her.

"That's the same age as me and my brother," said Mabel. "For some reason I thought you were younger. I begin to see possibilities for you, though I usually like my guys older."

"I can look older if I try, but it's not good for me to do that. I'm as old as I feel," said Steven.

"I know what you mean," said Mabel. "I want to stay a fun-loving kid as long as I can. My brother here wants to grow up too fast. He's twelve going on thirty."

"Just because I take things seriously..." said Dipper.

"It's different for me. It's all because of this gem I got from my mother," said Steven. He lifted his shirt with the yellow star on it and showed them the rosy crystal on his stomach.

"Ooh, a sparkly," said Mabel. "You bezazzled your belly. You skallywag, you've got my interest now for sure."

"Can we change the subject, please?" said Dipper. "We were talking about a monster investigation. What sort of monster are you looking for?"

"They can be almost any shape," said Steven. "Usually they have sharp points on them somewhere. The one I knew best had a single eye in the middle of its mouth."

"Sharp corners? Single eye? Are you thinking what I'm thinking, Mabel?" asked Dipper.

"Bill Cipher!" they both said together.

"Who is that?" asked Steven.

"A dream demon who's been after us," said Dipper. "He's shaped like the Eye in the Pyramid on a dollar bill. First he tried to steal a safe combination from our Grunkle Stan's mind, and then later he offered me a deal to learn the secrets of the universe from a laptop we found."

"A deal you took," said Mabel. "But I blame the lack of sleep."

"My days were taken up with your puppet play," said Dipper. "So I had to stay up all those nights."

"My bad," said Mabel.

"Let's just say I made a huge mistake and I nearly lost everything," said Dipper. "I did lose the laptop; Bill smashed it. He said I was too close to his secrets."

"Maybe Pearl could fix your laptop and we could find out whatever his secrets are. She's good with technology."

"How good?" asked Dipper.

"She rebuilt my Dad's car after it was smashed up," Steven said. "And she built a working rocket ship from spare parts that almost made it into space."

"Pretty good. That's better than our handyman could do," said Mabel.

"All right, we can let her try," said Dipper. "By the way, how did you happen to be looking for monsters around here in the first place?"

"The Crystal Gems detected a big energy surge here, the night of the sixteenth," said Steven.

"Hmm, what was going on then?" Dipper pondered. "We had just gotten the Mystery Shack fixed up again. That was the night Grunkle Stan borrowed my journal."

"I remember having a dream that night, that there was a glowing blue light all around me," said Mabel.

"I remember a dream like that," said Dipper. "I think it was that same night."

"The blue light might have been the energy surge. We need to find the other Gems and let them know about this lead," said Steven. "Come on, they're back in the woods this way."

"I'm with you, Steven," said Mabel. "Coming, Dipper?"

"Yes, I'm coming" said Dipper. "Maybe we can make some progress with our mysteries. Let me get the laptop, too. The disk drive might still be readable with the right equipment."

"If anyone can read it, Pearl can," said Steven.


	3. Portal to Beach City

**Portal to Beach City**

By the time the Pine twins arrived at the clearing to meet the Crystal Gems, the Manotaurs had already returned to their caves to lick their wounds (literally).

"Hey, Garnet, Amethyst, Pearl!" Steven called out. "I found some locals who may have seen the monster we're looking for."

"Wow," said Mabel. "It's awesome to meet real rock stars. I'm Mabel Pines and this is my brother, Dipper. You're too late for the Woodstick festival, but welcome to Gravity Falls anyway."

"Aw, too bad we missed the festival," said Amethyst.

"We prefer to be called Gems rather than Rocks," said Pearl. "We are the Crystal Gems."

"Tell us where to find the monster. We will defeat it and be on our way," said Garnet.

"If it's Bill Cipher you want, he's not that easy to find," said Dipper. "He's in the Dreamscape and he isn't solid, unless he's possessing someone."

"Like you," said Mabel.

Dipper shuddered. " Otherwise he just appears in dreams."

"Describe what you see in the dreams," said Pearl.

"He's a one-eyed yellow pyramid, with a bow tie and a black top hat," said Mabel. "A snappy-dressed Dorito."

Garnet frowned. "Sounds like a form Tourmaline would use."

"Bad news," said Amethyst.

"Who's Tourmaline?" asked Dipper.

"An insane Gem, a resistance leader," said Garnet.

"Tourmaline can do dream projections," Pearl said. "She has a physical gem to project from, but it could be hidden anywhere in this area. This could be a long and difficult investigation."

"They have another clue," said Steven. "Dipper, show them the laptop."

Dipper presented the broken laptop "Bill, er, Tourmaline smashed it up. I think the drive was in the process of being erased, but there's a chance the smashing stopped the erasing."

Pearl took it. "I can try to read it, but I'll need equipment I only have back home."

"When are you going back home?" Mabel asked. "And where do you live?"

"Right now," said Garnet.

"Beach City, Delaware. We should take you with us," said Steven.

"What?" said Dipper.

"Are you sure of that, Steven?" asked Amethyst.

"If you need to ask them questions, wouldn't it be safer?" asked Steven. "Tourmaline might come after them while we're gone."

"Wait a second," said Dipper. "You can't just take us out-of-state. That's kid-"

Amethyst had Mabel and Dipper, one under each arm, in an instant. Everyone went through the portal.

"...napping," said Dipper.

Amethyst released her hold. The twins looked around in astonishment.

"We've been abducted by aliens!" said Mabel. "Are you going to probe us? I hope so!"

"Don't worry," said Steven. "We're friendly, and I'm half human. We'll get you back home soon."

"Steven, why don't you show them around the island while I get to work on the laptop?" said Pearl.

"Sure," said Steven. "Come on, guys."

The twins stumbled after Steven. As they came out of the front door, Dipper turned around and looked up at the gigantic multi-armed statue that dominated the landscape.

"This is unbelievable," said Dipper. "Weird things are always happening to us, but this is the weirdest yet. It's like when we got pulled into the future."

"I sure know how to pick boyfriends, don't I?" said Mabel.

"Where would you like to go first?" asked Steven.

"Home," said Dipper.

"I'm kind of hungry after this big shock," said Mabel. "Could we get something to eat?"

Steven had grabbed his ukulele as they passed through the house, and now he began to sing:

"Mabel, this island has great food for you.  
>If you're hungry for pizza, try the Fish Stew.<br>As a special treat to stuff your face  
>Try the fry bits at Fryman's place.<br>But best of all from here to Mars  
>Is the Big Donut with Sadie and Lars."<p>

"You made up that song just for me?" said Mabel. "I think I do like you, half-alien abductor. I would like donuts, please."

"F-fries for me, I guess," said Dipper.

They got to Beach Citywalk Fries first.

"There's a guy here you ought to meet, Dipper," said Steven. "Hey Ronaldo, are you back there?"

A young man with curly yellow hair came to the counter. "Yes, Steven?"

"This is Dipper, a visitor from Gravity Falls, Oregon" said Steven. "He's a man after your own heart, an investigator of the paranormal."

"Have you seen my blog, 'Keep Beach City Weird'?" Ronaldo asked.

"We can't get much web access in Gravity Falls," said Dipper. "But I bet we could match your town for weirdness."

"Yeah? Come back in here and I'll show you my work. Maybe you could add a Gravity Falls page."

"Will you be all right, Mabel?" Dipper asked.

"I'll be fine. Go ahead and blog," said Mabel.

As Mabel and Steven continued walking toward the Big Donut, Steven greeted a young woman wearing glasses (or at least glasses frames).

"Hi, Connie," he said.

"Hi, Steven," said Connie. "Who is this with you?"

"I'm Mabel. Steven abducted me and we're on a date to get donuts."

"It's not a date, exactly," said Steven.

"But you did abduct her?" said Connie. "I'll leave you two alone."

She walked rapidly away.

"So, a jealous rival?" asked Mabel.

"She's my best friend. I'll have to explain to her later," said Steven.

They arrived at the donut shop.

"Hi Sadie. Hi Lars," said Steven.

"Hi, Steven," said Sadie with a smile.

"Hi, squirt," said Lars.

"Cool skin earrings," said Mabel to Lars. "How did you do that?"

"None of your business," said Lars.

"He did it by piercing and stretching them," said Sadie.

Lars made an angry noise. There seemed to be tension between him and Sadie.

"I wish I could do that," said Mabel.

"It takes months," said Sadie. "Would your mom allow that?"

"No," said Mabel. "I have to go home after the summer and then she'd kill me."

They ordered a dozen assorted donuts to take home to the Gems, and collected Dipper on the way back. Pearl was waiting for them when they arrived at the house.

"The disk is nearly completely erased, but I managed to read a bit of it," Pearl said. "I wanted to ask you if any of these names sound familiar."

She read to them, "We're about to start a new investigation. Once we get permission from the local landowner, we're going to dig for the source of the strange energies my detector picked up below ground. I'm dedicating this new laptop for this research. It looks like it could be a real breakthrough. Unlike my co-investigators, Despard and Margaret, I choose to record notes in a modern laptop instead of in hand-written journals. The Conifers are brilliant but eccentric, especially the sister."

"The laptop seems to be owned by a Fiddleford Hadron McGucket," said Pearl. Do you know him, or the Conifers?"

"We know McGucket," said Dipper. "Despard and Margaret Conifer, I'm not so sure about."

"They sound like fake names to me," said Mabel.

"Like fake names we might come up with for ourselves," said Dipper. "Initials D and M, like us. And a pine is a kind of conifer."

"Could the authors be... us?" asked Mabel.


End file.
